Increases in contributions to the state retirement system are expected to cost the district an estimated $1.8 million, he said.

The loss of a federal Adequate Education Grant could cost the district as much as $1.8 million, though Conrad said it is more likely to be in the $200,000 range.

The reduction of federal IDEA funds could transfer $230,000 for Title 1 schools onto the district's operating budget.

Conrad also pointed to an eight percent increase in health insurance costs and a possible decrease in Medicaid funding for the transportation of special needs students.

Wednesday night's Budget Committee meeting was a primer for a process that will take place through March. The superintendent noted that school administrators around the state are beginning to talk of "the new normal."

"We're not seeing in the foreseeable future any easy years in which we can say, 'Here's a year where we could easily be looking at increases in resources,'" he said.

In the worst case, Conrad said the district could eliminate positions; in the best case, the budget will have an unanticipated deficit. The actual decrease in outside funding will depend on negotiations happening in the state and U.S. Congress, he said.

Enrollment projections were also provided at the meeting. The current enrollment in Nashua schools is 11,895, nearly the same as last year. Over the next 10 years, the number is expected to dip to 11,333.

Conrad said these changes are based on birth rates, the aging population and the trend of young people leaving the state.

Assistant Superintendent Althea Sheaff presented elementary enrollment projections for the next school year - 5,480 students and 237.5 staff members. The district projects that enrollment will decline by 46 students.

It is predicted that 49 elementary classes will have 24 students or more, or 20 percent of classes.

Sheaff presented scenarios that could be put in place to address class size, an issue that has been high on the school board's agenda in recent months.

One option would put kindergarten classes at a maximum of 20 students per class, adding five teachers for $223,000. Another option would add eight teachers, with 23-student classes in kindergarten to second grade and 25-student classes in grades three to five.

Board member Sandra Ziehm noted that when looking at class sizes, English language learner students and others with special needs should be considered.

Sheaff said lowering class sizes is more effective in high-poverty areas.

Across Nashua's three middle schools, class sizes average 21.4 students. According to projections, that will increase to 21.8 next year.

At Fairgrounds Middle School, grade seven classes are projected to have 18 students per class, while sixth grade is projected to have 26.5.

At the high school level, classes are capped at 30 students. Foundation-level (low proficiency) classes are capped at 22 in the high school. Writing classes are capped at 25, science classes at 24.

The 2012-2013 budget approved last year was for $95.5 million, a 1.15 percent increase from the previous year. For the first time in three years, that budget did not eliminate positions, but added some seven posts.

The district has 908 teachers and a total of 1,008 employees.

A public hearing will be held on the school budget Feb. 21 at Nashua High North at 7 p.m.